Ethylene diammonium acetate

As the name implies, the first step of this domino process consists of a Knoevenagel condensation of an aldehyde or a ketone 2-742 with a 1,3-dicarbonyl compound 2-743 in the presence of catalytic amounts of a weak base such as ethylene diammonium diacetate (EDDA) or piperidinium acetate (Scheme 2.163). In the reaction, a 1,3-oxabutadiene 2-744 is formed as intermediate, which undergoes an inter- or an intramolecular hetero-Diels-Alder reaction either with an enol ether or an alkene to give a dihydropyran 2-745. [Pg.161]

DIAMMONIUM CHROMATE (7788-98-9) Not combustible but will enhance an existing fire. A powerful oxidizer. A heat- and shock-sensitive explosive. Contact with strong reducing agents such as hydrazine, alcohols, or ethers can cause explosion. Contact with water produces an alkaline solution, with evolution of free ammonia. Violent reaction with combustible materials, finely divided metals, organic substances. Aqueous solution is incompatible with organic anhydrides, acrylates, alcohols, aldehydes, alkylene oxides, substituted allyls, cellulose nitrate, cresols, caprolactam solution, epichlorohydrin, ethylene dichloride, isocyanates, ketones, glycols, nitrates, nitromethane, phenols, vinyl acetate exothermic decomposition with maleic anhydride. [Pg.387]